Original data is analogue with the digitised data having an hourly interval.

Fast delivery data at UHSLC

High frequency data at BODC

High frequency data at UHSLC

Real-time data available

Yes

Benchmarks

Benchmark relationships

All data are referred to a Datum Line (DL) associated with the tide gauge.
The Standard Mark (SM) is physically located near the tide gauge and is directly levelled to a First Order Bench Mark of the Geographical Survey Institute.
The SM is 4.407m above the DL and 3.044m above the TP (mean sea level of Tokyo Bay, or Peil).